/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */

/* LINTLIBRARY */

# include       <errno.h>
# include       <string.h>
# include       <stropts.h>

# include       "lp.h"
# include       "msgs.h"

int     Lp_prio_msg = 0;

static int      _mwrite ( MESG * md , char * msgbuf , int );

/*
 * mflush()
 *      return 0
 *              if it successfully writes all the queued message(s), or
 *              if some of them (errno is EAGAIN in this case).
 *      return -1 (with errno) when it failed.
 */

int
mflush(MESG *md)
{
        MQUE    *p;

        errno = 0;
        if (md == NULL || md->mque == NULL) {
                errno = ENXIO;
                return (-1);
        }

        while ((p = md->mque) != NULL) {
                if (_mwrite(md, p->dat->buf, p->dat->len) != 0)
                        return (errno == EAGAIN ? 0 : -1);

                /* mwrite successful, get the next and free this entry */
                md->mque = p->next;
                Free(p->dat->buf);
                Free(p->dat);
                Free(p);
        }

        return (0);
}

/*
 * mwrite()
 *      return 0
 *              if it successfully writes the messages, or
 *              if it has been queued  (errno is EAGAIN in this case)
 *                      and md->mque is updated.
 *      return -1 (with errno) when it failed.
 */

int mwrite ( MESG * md, char * msgbuf )
{
    short               size;
    MQUE *              p;
    MQUE *              q;

    errno = 0;
    if (md == NULL)
    {
        errno = ENXIO;
        return(-1);
    }
    if (msgbuf == NULL)
    {
        errno = EINVAL;
        return(-1);
    }

    size = stoh(msgbuf);

    if (LAST_MESSAGE < stoh(msgbuf + MESG_TYPE))
    {
        errno = EINVAL;
        return (-1);
    }
    if (md->mque)
        goto queue;     /* if there is a queue already, try to write all */

    if (_mwrite(md, msgbuf, size) == 0)
        return(0);

    if (errno != EAGAIN)
        return(-1);

        /*
         * fall through to queue the messages that cannot be sent now.
         */

queue:
    if ((p = (MQUE *)Malloc(sizeof(MQUE))) == NULL
        || (p->dat = (struct strbuf *)Malloc(sizeof(struct strbuf))) == NULL
        || (p->dat->buf = (char *)Malloc(size)) == NULL)
    {
        errno = ENOMEM;
        return(-1);
    }
    (void) memcpy(p->dat->buf, msgbuf, size);
    p->dat->len = size;
    p->next = 0;

    if ((q = md->mque) != NULL)
    {
        /* insert the new one to tail */
        while (q->next)
            q = q->next;
        q->next = p;

        while ((p = md->mque) != NULL)
        {
                if (_mwrite(md, p->dat->buf, p->dat->len) != 0) {
                        return (errno == EAGAIN ? 0 : -1);
                }

                /* mwrite successful, get the next and free this entry */
                md->mque = p->next;
                Free(p->dat->buf);
                Free(p->dat);
                Free(p);
        }
    }
    else
        md->mque = p;

    return(0);
}

int _mwrite ( MESG * md, char * msgbuf , int size )
{
    int                 flag = 0;
    struct strbuf       ctl;
    struct strbuf       dat;

    switch (md->type)
    {
        case MD_CHILD:
        case MD_STREAM:
        case MD_BOUND:
            if (size <= 0 || size > MSGMAX)
            {
                errno = EINVAL;
                return(-1);
            }

            ctl.buf = "xyzzy";
            ctl.maxlen = ctl.len = strlen(ctl.buf)+1;
            dat.buf = msgbuf;
            dat.maxlen = dat.len = size;
            flag = Lp_prio_msg;
            Lp_prio_msg = 0;    /* clean this up so there are no surprises */

            if (Putmsg(md, &ctl, &dat, flag) == 0)
                return(0);
            return(-1);

        case MD_SYS_FIFO:
        case MD_USR_FIFO:
            switch (write3_2(md, msgbuf, size))
            {
                case -1:
                    return(-1);
                case 0:
                    break;
                default:
                    return(0);
            }
            break;

        default:
            errno = EINVAL;
            return(-1);
    }
    return 0;
}